Model development, system identification, and control of a quadrotor helicopter

In this thesis a dynamical model is developed for general six degrees of freedom quadrotor vehicle. This is done modularly, and in a layered way. All component models are developed individually with various levels of dynamical complexity parameterized, themselves forming interconnected subsystems that together define the resulting vehicle model. The individual components and subsystems are hence relatively independent of the rest of the model as a whole and can, if desired, be easily extracted with varying levels of complexity selectable through parameters set by the user. Along with the more general vehicle hardware dynamics, existing on board electronics, a network architecture including infrared cameras and operating system based control, and wireless communication systems are modeled. All model parameters are identified with the theoretical background, experimental procedure, and numerical results given for each. Both nested-loop PID and LQR control schemes are developed and implemented, with the resulting performance of each compared to the other as well as the nonlinear simulation predictions. The LQR design is atypical in that it makes advantageous use of a systematic procedure to obtain appropriate cost weights, which capture design specifications while taking direct account of the system structure. The procedure leads to input-state coupling weights consistent with the dynamical limitations of the vehicle, which are key to the successful applicability of the LQR method for the quadrotor. All results are discussed with potential further work, issues and improvements highlighted.